Description and validation of an improved method to feed solitary bees (Osmia spp.) known amounts of pesticides

Pesticide exposure is an important driver of bee declines. Laboratory toxicity tests provide baseline information on the potential effects of pesticides on bees, but current risk assessment schemes rely on one species, the highly social honey bee, Apis mellifera, and there is uncertainty regarding the extent to which this species is a suitable surrogate for other pollinators. For this reason, Osmia cornuta and Osmia bicornis have been proposed as model solitary bee species in the EU risk assessment scheme. The use of solitary bees in risk assessment requires the development of new methodologies adjusted to the biology of these species. For example, oral dosing methods used with honey bees cannot be readily applied to solitary bees due to differences in feeding behaviour and social interactions. In this study, we describe the "petal method", a laboratory feeding method, and validate its use in acute and chronic exposure oral tests with Osmia spp. We conducted five experiments in which we compared the performance of several artificial flowers combining visual and olfactory cues against the petal method, or in which variations of the petal method were confronted. We then use the results of these experiments to optimize the feeding arenas and propose standardized methods for both acute and chronic exposure tests. The petal method provides high levels of feeding success, thus reducing the number of bees needed. It works with a wide variety of petal species and with both female and male Osmia spp., thus ensuring reproducibility across studies. To validate the use of the petal method in ecotoxicology tests, we assess the toxicity of a standard reference insecticide, dimethoate, in O. cornuta adults and determine LD50 values for this species. The petal method should facilitate the inclusion of solitary bees in risk assessment schemes therefore increasing the protection coverage of pesticide regulation.

Vitamin D supplementation and adverse skeletal and non-skeletal outcomes in individuals at increased cardiovascular risk: Results from the International Polycap Study (TIPS)-3 randomized controlled trial

BACKGROUND AND AIMS

Vitamin D has mostly been tested in Western populations. We examined the effect of high dose vitamin D in a population drawn predominantly from outside of Western countries.

METHODS AND RESULTS

This randomized trial tested vitamin D 60,000 IU monthly in 5670 participants without vascular disease but at increased CV risk. The primary outcome was fracture. The secondary outcome was the composite of CV death, myocardial infarction stroke, cancer, fracture or fall. Death was a pre-specified outcome. Mean age was 63.9 years, and 3005 (53.0%) were female. 3034 (53.5%) participants resided in South Asia, 1904 (33.6%) in South East Asia, 480 (8.5%) in South America, and 252 (4.4%) in other regions. Mean follow-up was 4.6 years. A fracture occurred in 20 participants (0.2 per 100 person years) assigned to vitamin D, and 19 (0.1 per 100 person years) assigned to placebo (HR 1.06, 95% CI 0.57-1.99, p-value = 0.86). The secondary outcome occurred in 222 participants (1.8 per 100 person years) assigned to vitamin D, and 198 (1.6 per 100 person years) assigned to placebo (HR 1.13, 95% CI 0.93-1.37, p = 0.22). 172 (1.3 per 100 person years) participants assigned to vitamin D died, compared with 135 (1.0 per 100 person years) assigned to placebo (HR 1.29, 95% CI 1.03-1.61, p = 0.03).

CONCLUSION

In a population predominantly from South Asia, South East Asia and South America, high-dose vitamin D did not reduce adverse skeletal or non-skeletal outcomes. Higher mortality was observed in the vitamin D group.

REGISTRATION NUMBER

NCT01646437.

Left ventricular high frame rate echo-particle image velocimetry: feasibility and comparison with conventional echocardiography

Funding Acknowledgements

Type of funding sources: None.

Introduction

Echo-Particle Image Velocimetry (echoPIV) tracks speckle patterns from ultrasound contrast agent (UCA) microbubbles injected intravenously, being less angle-sensitive than colour Doppler. One limitation of conventional echoPIV is the inability to accurately resolve high velocities, because of relatively low frame rates.  In contrast, high frame rate (HFR) echoPIV enables tracking of fast flow in the left ventricle (LV).

Purpose

To investigate the feasibility and precision of HFR echoPIV in patients.

Methods

19 heart failure patients were included. UCA was infused with a dedicated pump. HFR contrast images were acquired, in apical long axis view (ALAX, ensuring simultaneous visualization of LV inflow and outflow), using a fully-programmable research ultrasound system, with a phased array probe. In the same session, complete echocardiographic studies were obtained using a clinical ultrasound system, with a matrix array probe, including LV UCA. Non-contrast pulsed-wave (PW) Doppler were also obtained in ALAX (Figure 1) from the mitral valve tips (inflow) and the LV outflow tract (outflow). HFR echoPIV image quality and tracking were assessed offline by two independent observers. The peak velocity of the inflow and outflow were determined by the automated tracking algorithm of the HFR echoPIV, and measured by the peak modal velocity of the conventional PW. These velocities were compared using Pearson’s correlations and Bland-Altman plots. All patients gave their informed consent. The study was approved by the institutional review board.

Results

Conventional echo image quality was good in 12 (63%), medium in 5 (26%) and bad in 2 (11%). EchoPIV tracking was good in 12 (63%), medium in 2 (10%) and bad in 5 (26%). In the 12 patients where echoPIV tracking was good, the direction and velocity of intracavitary vortices could be visualized (Figure 1). The inflow velocity could be determined by echoPIV  in 17/19 (89%), and outflow in 14/19 (74%). EchoPIV tended to underestimate the maximal velocity as determined by PW (Figure 2), with a bias of 0.19 m/s (inflow) and 0.28 m/s (outflow). This negative bias is expected as the PW is assessing maximum velocity in the interrogation kernel whereas echoPIV returns the mean velocity. The correlation of the two methods was good for the inflow (R2 = 0.77, p < 0.001) and moderate for the outflow (R2 = 0.54, p < 0.001). This may be explained by the position of the LV outflow tract deeper in the image, leading to increased attenuation, clutter and reduced lateral resolution.

Conclusion

HFR echoPIV has comparable feasibility to routine echocardiography, and the ability to correctly estimate intraventricular flow velocity. It can provide in one acquisition all the functional information that can be detected by routine echocardiography, PW and color Doppler, as well as contrast. It succeeds in surpassing the shortcomings of Doppler (angle dependency) and classical contrast imaging (low frame rate). Abstract Figure 1: HFR echoPIV in study patients  Abstract Figure 2: study results

33 ARE CLINICAL TRIALS RANDOMISING HOUSEHOLDS TO LIFESTYLE INTERVENTIONS FOR THE PREVENTION OF COGNITIVE DECLINE FEASIBLE?

Background

Dementia is increasing in prevalence worldwide. Several lifestyle factors have been identified as targets for dementia prevention, which may be more effective if targeted at households instead of an individual. To date there have been no clinical trials randomising households to lifestyle interventions of sleep, diet and/or physical activity to prevent cognitive decline. To inform future studies, qualitative approaches can give valuable in-depth insights into the values and beliefs of all household members towards behavioural change.

Methods

Semi structured interviews were carried out among eight households affected by cognitive impairment. Interview content was analysed, and important themes identified.

Results

Eighteen participants were interviewed within household pods. Among those, eight had cognitive impairment and the remainder were spouses or first-degree relatives living in the same home. Several themes of interest emerged including household members without dementia were more likely to report poor sleep habits; sleep was perceived the hardest behaviour to change; although most participants had healthy diets, most were interested in making a change and felt there was a strong link with nutrition and cognition; physical activity is challenging to adapt due to lack of motivation and focus when individuals are cognitively impaired and motivation to pursue physical activity in households centred on relaxation and social interaction.

Conclusion

This study identified beliefs and preferences of households towards lifestyle intervention trials. Barriers to study participation including risk of harm, complexity of intervention and deviation from routine emerged during discussions. Findings from this study should be used to inform future clinical trial protocols and future qualitative studies should explore acceptability and feasibility of digital intervention applications.

Results from HART-c: innovations in prehospital triage for acute cardiac symptoms, a multicentre prospective study

Introduction

Cardiac symptoms are one of the most prevalent reasons for emergency department (ED) visits [1], however most of these patients do not have acute cardiovascular disease. This leads to ED overcrowding which subsequently leads to worse patient outcomes and increased costs [2,3]. Attempts to reduce overcrowding have focused mostly on in-hospital triage. The Hollands-midden Acute Regional Triage – cardiology (HART-c) study uses a newly developed triage platform which includes live monitoring, real-time admission capacity, in-hospital data and cardiologist consultation for improved prehospital triage.

Purpose

The HART-c study aims to safely increase the percentage of patients with cardiac symptoms not referred to the hospital after emergency medical service (EMS) consultation.

Methods

Patients aged 18 years or older visited by the EMS for cardiac symptoms were included in the region Hollands-Midden from September 2019 till March 2020 (non-COVID period) and compared with the year earlier. Patients were excluded when primary PCI was indicated. EMS consultation consisted of medical history, physical examination, vital parameters and ECG. All data were transferred to a newly developed platform combining pre-hospital data, shown in real-time, and hospital data, such as medical records and admission capacity. The paramedic contacted an on-call triage cardiologist and decided whether admission was necessary and, if so, which regional hospital was most appropriate (figure 1). The study objective was defined as the percentage of patients not referred to the hospital after EMS consultation. Safety of the triage method was defined in the non-referred patients in the intervention as the percentage of MACE (death and acute coronary syndrome) 30 days after non-referral.

Results

In the intervention group 1755 patients (age 69±15 years, 53% men), and in the control group 1629 patients (age 68±15 years, 53% men) were consulted by the EMS during the HART-c study. In the intervention group 11.4% of patients consulted to the EMS were left at home, compared to 5.5% in the control group (figure 2). Logistic regression was performed to evaluate the effect of the triage intervention. The model was corrected for gender, age and seasonal changes. The chance of being left at home after EMS consultation was 2.29 (95% CI 1.73–3.02, p<0.001) times higher in the intervention group compared to the control. All patients left at home in the intervention group and their GP's were contacted for adverse events, after case-by-case review the MACE rate was <1%. Furthermore a decrease in interhospital transfers was seen, from 206 in the intervention to 173 in the control.

Conclusion

Implementation of an innovative triage method successfully increased the percentage of patients with cardiac symptoms safely left at home.

Funding Acknowledgement

Type of funding sources: None. Triage without (A) and with (B) platformNon-referral in intervention and control

Toxicity of the insecticide sulfoxaflor alone and in combination with the fungicide fluxapyroxad in three bee species

The sulfoximine insecticide sulfoxaflor is regarded as a potential substitute for neonicotinoids that were recently banned in the EU due to their side effects on bees. Like neonicotinoids, sulfoxaflor acts as a competitive modulator of nicotinic acetylcholine receptors. In agricultural environments, bees are commonly exposed to combinations of pesticides, and neonicotinoids are known to interact synergistically with fungicides. The objective of our study is to assess the acute oral toxicity of sulfoxaflor alone and in combination with a single dose of fluxapyroxad, a succinate dehydrogenase inhibitor (SDHI) fungicide, in three bee species: Apis mellifera, Bombus terrestris and Osmia bicornis. Because synergism may be dose-dependent, we tested a range of sulfoxaflor doses. Synergistic effects were assessed using three different approaches: Bliss criterion of drugs independence, ratio test comparing LD50s and model deviation ratio. Osmia bicornis was the most sensitive species to sulfoxaflor and both O. bicornis and A. mellifera showed significant synergism between the insecticide and the fungicide. For the most part, these synergistic effects were weak and only occurred at early assessment times and intermediate sulfoxaflor doses. The potential ecological relevance of these effects should be confirmed in field and/or cage studies. Overall, our laboratory results demonstrate that sulfoxaflor is somewhat less toxic than the recently banned neonicotinoids imidacloprid, thiamethoxam and clothianidin, but much more toxic than other neonicotinoids (acetamiprid, thiacloprid) still in use in the EU at the time this study was conducted.

Emergency medical services evaluations for chest pain during first COVID-19 lockdown in Hollands-Midden, the Netherlands

Objective

To assess whether the COVID-19 lockdown in 2020 had negative indirect health effects, as people seem to have been reluctant to seek medical care.

Methods

All emergency medical services (EMS) transports for chest pain or out-of-hospital cardiac arrest (OHCA) in the Dutch region Hollands-Midden (population served > 800,000) were evaluated during the initial 6 weeks of the COVID-19 lockdown and during the same time period in 2019. The primary endpoint was the number of evaluated chest pain patients in both cohorts. In addition, the number of EMS evaluations of ST-elevation myocardial infarction (STEMI) and OHCA were assessed.

Results

During the COVID-19 lockdown period, the EMS evaluated 927 chest pain patients (49% male, age 62 ± 17 years) compared with 1041 patients (51% male, 63 ± 17 years) in the same period in 2019, which corresponded with a significant relative risk (RR) reduction of 0.88 (95% confidence interval (CI) 0.81–0.96). Similarly, there was a significant reduction in the number of STEMI patients (RR 0.52, 95% CI 0.32–0.85), the incidence of OHCA remained unchanged (RR 1.23, 95% CI 0.83–1.83).

Conclusion

During the first COVID-19 lockdown, there was a significant reduction in the number of patients with chest pain or STEMI evaluated by the EMS, while the incidence of OHCA remained similar. Although the reason for the decrease in chest pain and STEMI consultations is not entirely clear, more attention should be paid to the importance of contacting the EMS in case of suspected cardiac symptoms in possible future lockdowns.

Supplementary Information

The online version of this article (10.1007/s12471-021-01545-y) contains supplementary material, which is available to authorized users.

Closed-chest measurement of diastolic and systolic shear wave speed to assess myocardial stiffness

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Research Foundation Flanders (FWO): grant 1211620N TTW – Dutch Heart Foundation partnership program "Earlier recognition of cardiovascular diseases": project number 14740

Background

Echocardiographic shear wave elastography (SWE) encompasses all ultrasound techniques tracking shear wave (SW) motion in the cardiac wall, of which the propagation speed is linked to the intrinsic mechanical properties. SWs can be induced naturally, for example by valve closure, or externally by using an acoustic radiation force (ARF). Although the latter is technically more demanding, it enables instantaneous stiffness assessment throughout the entire cardiac cycle (fig. a). However, it is unknown how factors such as cardiac loading and contractility, next to intrinsic mechanical properties, affect ARF-based SW speeds.

Purpose

We performed transthoracic SWE measurements in pigs to study the effects of hemodynamic alterations, inotropic state and myocardial infarction (MI) on diastolic and systolic SW speeds.

Methods

Different cardiac conditions were considered in three pigs: (i) baseline (BL), (ii) preload decrease (PD), (iii) afterload increase (AI), (iv) preload increase (PI), (v) administration of dobutamine (DOB), (vi) BL2, (vii) MI through 60-100 min. occlusion of the LAD and (viii) 40 min. reperfusion (REP). For each condition, transthoracic high frame rate ARF-based SWE acquisitions were taken in a parasternal long-axis view with a research ultrasound system. SWs were induced in the septum at 34 Hz during 1.5 s to track SW speeds throughout the cardiac cycle (fig. a&b). Systolic and diastolic SW speeds were determined from the 10% highest and lowest median values per condition, respectively. Left ventricular pressure-volume (PV) loops were recorded to estimate end-diastolic pressure (EDP), end-systolic pressure (ESP) and passive chamber stiffness (dPdV). dPdV was determined as the slope of the tangent to the fitted end-diastolic PV relationship at mean ED volume. Linear regressions and Pearson’s correlation coefficients were computed.

Results

Diastolic SW speed was correlated to EDP for conditions with changes in loading, and to dPdV for conditions with changes in chamber stiffness (fig. c).  Both relationships were significant, with a moderate positive correlation for EDP (R = 0.48, p = 0.02) and a strong positive correlation for dPdV (R = 0.76, p < 0.01). Furthermore, the observed change in diastolic SW speed was smaller when altering EDP compared to dPdV (0.4 m/s vs. 1.0 m/s). For systolic SW speed, very strong positive correlations were found with ESP (R = 0.91, p < 0.01), and with dPdV (R = 0.81, p < 0.01) in fig. d.

Conclusion

This study shows that both diastolic and systolic SW speed are related to passive chamber stiffness. Moreover, loading also influenced systolic SW speed and, to a lesser extent, diastolic SW speed, presumably because of material nonlinearity. Systolic SW speed is linked to contractility as well. Thus, while SWs after valve closure occur at a certain moment in the cardiac cycle, the timing of ARF-based SWs can be chosen such to assess specific aspects of the cardiac (structural and functional) status.

Abstract Figure.

Efficacy and safety of low-dose rivaroxaban on top of aspirin in patients with polypharmacy and multimorbidity: an analysis from the COMPASS trial

Background

In patients with coronary or peripheral artery disease, intensified antithrombotic therapy with aspirin plus low dose rivaroxaban reduced cardiovascular outcomes compared with aspirin alone. Polypharmacy and multimorbidity are frequent in patients with vascular disease and are often perceived as barriers to more intensive pharmacotherapy by both patients and physicians.

Purpose

To report cardiovascular outcomes and the efficacy, safety, and net benefit of low dose rivaroxaban plus aspirin in patients with stable vascular disease by the number of concomitant cardiovascular drugs and by the number of comorbidities.

Methods

We reported ischemic events (cardiovascular death, stroke, or MI), major bleeding (ISTH modified criteria), and a prespecified net clinical outcome in participants from the randomised, double-blind COMPASS study by number of cardiovascular medications (0–2, 3, 4, 5–7) and by number of concomitant medical conditions. We compared rates and hazard ratios of patients treated with rivaroxaban plus aspirin vs aspirin alone by category of number of medications and concomitant conditions and tested for interaction between polypharmacy and multimorbidity and antithrombotic regimen.

Results

Although patients with polypharmacy and multimorbidity have a higher risk of cardiovascular events (Figure) those who required many cardiovascular drugs derived the largest absolute reduction in the net clinical outcome when adding rivaroxaban on top of aspirin. The relative efficacy, safety, and net clinical benefit of adding low-dose rivaroxaban to aspirin in patients with stable vascular diseases were not affected by the number of cardiovascular drugs or by the number of comorbidities. Multimorbidity, but not polypharmacy, was related with a higher risk of major bleeding.

Conclusion

Addition of low-dose rivaroxaban conveyed a benefit irrespective of the number of concomitant drugs or comorbid conditions. Multiple comorbidities and/or polypharmacy should not dissuade the addition of low-dose rivaroxaban to aspirin in otherwise eligible patients.

Figure 1

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): The COMPASS trial was funded by Bayer AG.

P1538 Light exercise may induce an increase in the propagation velocity of naturally occurring shear waves

Background

Shear waves (SW) are induced in the myocardium by the closure of the valves. Recent studies show variations in their propagation velocity with age, gender or pathology. However, these valve-induced waves occur during relaxation and contraction. This means that the instantaneous SW velocity, as measure for stiffness, might not only depend on the intrinsic elastic properties of the relaxed myocardium, but also on its contractility and the exact moment of valve closure. The latter can change with heart rate and loading conditions, which could induce variance in measurement.

Purpose

This study aimed to investigate the effect of light exercise on the propagation velocity of naturally occurring shear waves.

Methods

Ten healthy volunteers underwent high frame rate (over 500 Hz) color TDI studies at rest and during light physiological stress (handgrip exercise). Shear wave velocities were averaged over several heart beats. Values obtained were compared by using the Wilcoxon signed ranks test and a Bland-Altman analysis.

Results

The light physiological exercise test induced a small but statistically significant rise in diastolic blood pressure and heart rate (table). The shear wave velocity after aortic valve closure (ASW) could be quantified in each subject at rest and during stress. The shear wave tracking after mitral valve closure (MSW) was only feasible for 8 subjects at rest and 6 during stress. There was an average difference of 0.4 ± 0.3 m/s (LOA= -0.18 to 0.97 m/s) between stress and rest measurements for the ASW velocity, which was statistically significant(p = 0.01, Figure). For the MSW the average difference was 0.02 ± 0.5 m/s (LOA= -1.02 to 1.06 m/s), p = 0.9.

Conclusion

We observed a statistically significant rise in the shear wave velocity after aortic valve closure but not after mitral closure during a light exercise. Although the statistical power of this study is relatively small, the results may suggest that naturally occurring shear waves velocity can be influenced by heart rate and loading conditions.

Table Parameter Rest Stress P Age [yr] 30 ± 6 - - BMI [kg/m2] 22 ± 2 - - Heartrate [bpm] 62 ± 7 67 ± 8 <0.01 Systolic blood pressure [mmHg] 106 ± 13 110 ± 10 0.08 Diastolic blood pressure [mmHg] 62 ± 9 67 ± 9 0.01 Aortic shear wave velocity [m/s] 3.26 ± 0.4 3.65 ± 0.7 0.01 Mitral shear wave velocity [m/s] 4.56 ± 0.7 4.83 ± 0.8 0.9

Abstract P1538 Figure

Method of Determination of Appropriate Heat Treatment of Animal Meal by Immunoassay Developed for Detection of Cooked Beef: Interlaboratory Study

An interlaboratory trial was conducted for the validation of an enzyme-linked immunosorbent assay (ELISA) method for determination of appropriate heat treatment of animal meal. A commercially available ELISA test kit developed for the identification of beef in cooked food was used in the study. Twelve laboratories from 7 European countries examined 2 different analytical protocols to establish the most appropriate analytical method. Three different samples were used, 2 animal waste materials sterilized at 129 and 134°C (wet conditions), respectively, and a meat and bone meal material processed at dry conditions (maximum temperature, 140°C). Statistical evaluation applying t-statistics showed that the animal meal treated according to European legislation (>133°C) was clearly distinguishable from the 2 other test materials at a 99% confidence level using both analytical protocols. This method can be considered as a complementary test to the immunoassay developed for the detection of pork in cooked food that is already applied in routine analysis for the surveillance of rendering plants.

4112Risk factors and clinical outcomes in chronic CAD and PAD: an analysis of the randomized, double-blind COMPASS trial

Background

Patients with coronary artery disease (CAD) and peripheral artery disease (PAD) are at high risk for cardiovascular death and ischemic events. Secondary prevention requires both optimal control of modifiable cardiovascular risk factors and antithrombotic therapy. The COMPASS study showed a reduction in ischemic events in patients treated with the combination of low-dose rivaroxaban and aspirin, compared with aspirin alone. However, the impact of intensifying antithrombotic therapy by baseline risk factor control is not well studied.

Objective

To study the association between baseline risk factor status and outcomes, and the effects of treatment with low-dose rivaroxaban and aspirin compared with aspirin alone according to baseline risk factors, in a large contemporary population of patients with CAD or PAD.

Methods

We studied ischemic events (cardiovascular death, stroke, or MI) in participants from the randomised, double blind COMPASS trial in relation to baseline blood pressure, smoking status, cholesterol level, presence of diabetes, body mass index, and level of physical activity, as well as by the number of cardiovascular risk factors (0–1, 2, 3, 4, or 5–6). Within each risk factor category, we compared rates and hazard ratios of patients treated with rivaroxaban plus aspirin vs aspirin alone and tested for interaction between the treatment effect of rivaroxaban and risk factor status.

Results

Baseline information on all six risk factors was available in 27,117 (99%) patients. Each risk factor was associated with increased risk of ischemic events (Figure 1, panel A). Patients with 5 or 6 risk factors had more than 2-fold higher rates of ischemic events (HR 2.36; 95% CI: 1.80–3.10) and of cardiovascular death (HR 2.22; 1.48–3.33) compared with patients with 0 or 1 risk factor. The addition of low-dose rivaroxaban on top of aspirin reduced event rates independently of number of risk factors (p for interaction 0.93) (Figure 1, panel B). The largest absolute benefit of low-dose rivaroxaban was seen in patients with the greatest number of risk factors.

Figure 1

Conclusion

More favourable baseline risk factor status and the use of low-dose rivaroxaban were both independently associated with lower risk of ischemic events. Patients at highest risk, based on number of baseline risk factors, derive the largest absolute benefit of the combination of rivaroxaban and aspirin.

Acknowledgement/Funding

The COMPASS trial was sponsored by Bayer AG. The sponsor did not influence the analysis plan, drafting of abstract, or the decision to submit

2180Estimating individual lifetime benefit and bleeding risk of adding rivaroxaban to aspirin for patients with stable cardiovascular disease: results from the COMPASS trial

Background

The Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) trial has demonstrated that adding low-dose rivaroxaban to aspirin in patients with stable atherosclerotic disease on average reduces recurrence of cardiovascular disease (CVD) events, but increases the risk of major bleeding. For clinical practice, it is important to be able to weigh the absolute benefit from the intervention in terms of lower cardiovascular risk against the absolute increase in risk for major bleeding.

Purpose

The aim of this study was to estimate the individual lifetime benefit and harm of adding low-dose rivaroxaban to aspirin in patients with stable cardiovascular disease by predicting individual months free from CVD events gained and individual months free from major bleeding lost.

Methods

Analyses were based on data of patients with established CVD in the COMPASS trial (n=27,390) and SMART prospective cohort study (n=8,139). The externally validated lifetime SMART-REACH model for recurrent CVD was used to predict life expectancy free of stroke and myocardial infarction, based on the following predictors: sex, current smoking, diabetes mellitus, systolic blood pressure, total cholesterol, creatinine, number of locations of CVD, history of atrial fibrillation, and history of congestive heart failure. A new Fine & Gray competing-risk adjusted Cox proportional hazard model was derived in the COMPASS study population for prediction of life expectancy free from major bleeding, including the same predictors as the SMART-REACH model and additionally ethnicity, geographical region, and history of bleeding requiring transfusion. These lifetime estimates were then combined with hazard ratios from the COMPASS trial to estimate lifetime treatment effects from adding low-dose rivaroxaban to aspirin, expressed in terms of 1) months free from stroke or myocardial infarction gained, and 2) months free from major bleeding lost.

Results

External goodness-of-fit of the SMART-REACH model in the COMPASS study was sufficient. The newly developed major bleeding risk model also showed sufficient external goodness-of-fit in the SMART cohort. The median predicted individual gain in life-expectancy free of stroke or MI from added low-dose rivaroxaban was 16 months (range 1–48 months), while the median predicted individualized lifetime lost in terms of major bleeding was 2 months (range 0–20 months) (Figure 1A). Predicted benefit was higher than predicted harm in more than 90% of the study population. An interactive calculator for use in clinical practice will be made available (example in figure 1B).

Figure 1

Conclusions

There is a wide distribution in lifetime gain and harm from adding low-dose rivaroxaban to aspirin in individual patients with stable CVD. Using these lifetime models, benefits and bleeding risk can be weighed for and with each individual patient, to support treatment decision making in clinical practice.

Skin-associated lactic acid bacteria from North American bullfrogs as potential control agents of Batrachochytrium dendrobatidis

The fungal pathogen Batrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis and has been a key driver in the catastrophic decline of amphibians globally. While many strategies have been proposed to mitigate Bd outbreaks, few have been successful. In recent years, the use of probiotic formulations that protect an amphibian host by killing or inhibiting Bd have shown promise as an effective chytridiomycosis control strategy. The North American bullfrog (Lithobates catesbeianus) is a common carrier of Bd and harbours a diverse skin microbiota that includes lactic acid bacteria (LAB), a microbial group containing species classified as safe and conferring host benefits. We investigated beneficial/probiotic properties: anti-Bd activity, and adhesion and colonisation characteristics (hydrophobicity, biofilm formation and exopolysaccharide-EPS production) in two confirmed LAB (cLAB-Enterococcus gallinarum CRL 1826, Lactococcus garvieae CRL 1828) and 60 presumptive LAB (pLAB) [together named as LABs] isolated from bullfrog skin.We challenged LABs against eight genetically diverse Bd isolates and found that 32% of the LABs inhibited at least one Bd isolate with varying rates of inhibition. Thus, we established a score of sensitivity from highest (BdGPL AVS7) to lowest (BdGPL C2A) for the studied Bd isolates. We further reveal key factors underlying host adhesion and colonisation of LABs. Specifically, 90.3% of LABs exhibited hydrophilic properties that may promote adhesion to the cutaneous mucus, with the remaining isolates (9.7%) being hydrophobic in nature with a surface polarity compatible with colonisation of acidic, basic or both substrate types. We also found that 59.7% of LABs showed EPS synthesis and 66.1% produced biofilm at different levels: 21% weak, 29% moderate, and 16.1% strong. Together all these properties enhance colonisation of the host surface (mucus or epithelial cells) and may confer protective benefits against Bd through competitive exclusion. Correspondence analysis indicated that biofilm synthesis was LABs specific with high aggregating bacteria correlating with strong biofilm producers, and EPS producers being correlated to negative biofilm producing LABs. We performed Random Amplified Polymorphic DNA (RAPD)-PCR analysis and demonstrated a higher degree of genetic diversity among rod-shaped pLAB than cocci. Based on the LAB genetic analysis and specific probiotic selection criteria that involve beneficial properties, we sequenced 16 pLAB which were identified as Pediococcus pentosaceus, Enterococcus thailandicus, Lactobacillus pentosus/L. plantarum, L. brevis, and L. curvatus. Compatibility assays performed with cLAB and the 16 species described above indicate that all tested LAB can be included in a mixed probiotic formula. Based on our analyses, we suggest that E. gallinarum CRL 1826, L. garvieae CRL 1828, and P. pentosaceus 15 and 18B represent optimal probiotic candidates for Bd control and mitigation.

Clinical prediction of thrombectomy eligibility: A systematic review and 4-item decision tree

BACKGROUND

A clinical large anterior vessel occlusion (LAVO)-prediction scale could reduce treatment delays by allocating intra-arterial thrombectomy (IAT)-eligible patients directly to a comprehensive stroke center.

AIM

To subtract, validate and compare existing LAVO-prediction scales, and develop a straightforward decision support tool to assess IAT-eligibility.

METHODS

We performed a systematic literature search to identify LAVO-prediction scales. Performance was compared in a prospective, multicenter validation cohort of the Dutch acute Stroke study (DUST) by calculating area under the receiver operating curves (AUROC). With group lasso regression analysis, we constructed a prediction model, incorporating patient characteristics next to National Institutes of Health Stroke Scale (NIHSS) items. Finally, we developed a decision tree algorithm based on dichotomized NIHSS items.

RESULTS

We identified seven LAVO-prediction scales. From DUST, 1316 patients (35.8% LAVO-rate) from 14 centers were available for validation. FAST-ED and RACE had the highest AUROC (both >0.81, p < 0.01 for comparison with other scales). Group lasso analysis revealed a LAVO-prediction model containing seven NIHSS items (AUROC 0.84). With the GACE (Gaze, facial Asymmetry, level of Consciousness, Extinction/inattention) decision tree, LAVO is predicted (AUROC 0.76) for 61% of patients with assessment of only two dichotomized NIHSS items, and for all patients with four items.

CONCLUSION

External validation of seven LAVO-prediction scales showed AUROCs between 0.75 and 0.83. Most scales, however, appear too complex for Emergency Medical Services use with prehospital validation generally lacking. GACE is the first LAVO-prediction scale using a simple decision tree as such increasing feasibility, while maintaining high accuracy. Prehospital prospective validation is planned.

Efficacy of a multidisciplinary approach on postoperative morbidity and mortality of elderly patients with hip fracture

STUDY OBJECTIVE

We evaluated the efficacy of a multidisciplinary approach to reduce postoperative complications and 1-year mortality in patients, undergoing hip fracture surgery and the impact of surgical delay on mortality.

DESIGN

A non-randomized intervention study with a historical control group (CG).

SETTING

During the hospital stay of patients undergoing hip fracture surgery and subsequent follow-up during 12 months post-discharge.

PATIENTS

240 patients undergoing hip fracture surgery were included in the CG. 272 patients were included in the intervention group (IG).

INTERVENTIONS

CG patients received the standard care given at our hospital. Patients in the IG received a new model of multidisciplinary approach to care.

MEASUREMENTS

The following variables were collected: study group, age, gender, ASA physical status, comorbidity, type of fracture, type of anaesthesia, surgical delay, postoperative complications, hospital stay, destination after discharge and postoperative mortality.

MAIN RESULTS

512 patients (CG = 240; IG = 272). Mean age was 83.8 years in CG and 84.9 years in IG. Patients in the IG had a worse health status according to ASA (III-IV: 68.8% vs 51.7%; p < 0.001) and took more drugs (p < 0.001). Surgery was performed within 48 h of admission in 55.1% of patients of the IG (38.3% CG; p < 0.001). Incidence of postoperative complications (67.3% IG vs 76.2% CG p = 0.025) and hospital stay was shorter in the IG (p < 0.001). A surgical delay of >48 h (HR = 0.61; CI95%: 0.42-0.88) and allocation to the IG (HR = 0.64; CI95%: 0.44-0.93) were the protective factors for mortality.

CONCLUSIONS

The multidisciplinary approach could be associated with a decrease in postoperative complications, hospital stay and mortality. Surgical delay may not increase the risk of mortality. The main objective in the management of these patients should be the optimization of their general health status before surgery rather than surgical delay.

Relation of Plasma Coagulation Factor VII and Fibrinogen to Carotid Artery Intima-Media Thickness

Plasma clotting factor VII and plasma fibrinogen have been claimed as independent risk factors for occlusive cardiovascular disease. The aim of this study was to investigate whether these coagulation parameters affect early atherosclerosis, additional to their possible effect on arterial thrombosis.

We used high-resolution quantitative ultrasonography to measure carotid intima-media thickness in 121 healthy volunteers, aged 18 to 56 years. It has previously been demonstrated that an increased artery wall thickness is seen in advanced atherosclerosis. To validate our methodology for relatively young individuals, we assessed the association of intima-media thickness with the risk-factor status of our subjects, by including classical cardiovascular risk factors, e. g. age, sex, serum cholesterol, smoking habits and blood pressure. Thereafter, we studied the effect of factor VII and fibrinogen plasma levels on carotid intimamedia thickness, as well as that of polymorphisms of the factor VII and fibrinogen genes.

All classical risk factors except smoking and family history were associated with intima-media thickness. When adjusted for by multivariate linear regression analysis, age, blood pressure and cholesterol appeared to be independent determinants of intima-media thickness. Factor VII and fibrinogen levels showed no association in multivariate analysis with intima-media thickness. We conclude that artery wall thickness measurement by ultrasound is a useful tool to investigate the role of clotting factors in early atherosclerosis. Factor VII and fibrinogen levels in young and middle-aged volunteers have no association with early artherosclerotic vessel wall changes.

Escherichia coli: an old friend with new tidings

Escherichia coli is one of the most-studied microorganisms worldwide but its characteristics are continually changing. Extraintestinal E. coli infections, such as urinary tract infections and neonatal sepsis, represent a huge public health problem. They are caused mainly by specialized extraintestinal pathogenic E. coli (ExPEC) strains that can innocuously colonize human hosts but can also cause disease upon entering a normally sterile body site. The virulence capability of such strains is determined by a combination of distinctive accessory traits, called virulence factors, in conjunction with their distinctive phylogenetic background. It is conceivable that by developing interventions against the most successful ExPEC lineages or their key virulence/colonization factors the associated burden of disease and health care costs could foreseeably be reduced in the future. On the other hand, one important problem worldwide is the increase of antimicrobial resistance shown by bacteria. As underscored in the last WHO global report, within a wide range of infectious agents including E. coli, antimicrobial resistance has reached an extremely worrisome situation that ‘threatens the achievements of modern medicine’. In the present review, an update of the knowledge about the pathogenicity, antimicrobial resistance and clinical aspects of this ‘old friend’ was presented.

Effect of viral suppression on hepatic venous pressure gradient in hepatitis C with cirrhosis and portal hypertension

Portal hypertension is a predictor of liver-related clinical events and mortality in patients with hepatitis C and cirrhosis. The effect of interferon-free hepatitis C treatment on portal pressure is unknown. Fifty patients with Child-Pugh-Turcotte (CPT) A and B cirrhosis and portal hypertension (hepatic venous pressure gradient [HVPG] >6 mm Hg) were randomized to receive 48 weeks of open-label sofosbuvir plus ribavirin at Day 1 or after a 24-week observation period. The primary endpoint was sustained virologic response 12 weeks after therapy (SVR12) in patients who received ≥1 dose of treatment. Secondary endpoints included changes in HVPG, laboratory parameters, and MELD and CPT scores. A subset of patients was followed 48 weeks posttreatment to determine late changes in HVPG. SVR12 occurred in 72% of patients (33/46). In the 37 patients with paired HVPG measurements at baseline and the end of treatment, mean HVPG decreased by -1.0 (SD 3.97) mm Hg. Nine patients (24%) had ≥20% decreases in HVPG during treatment. Among 39 patients with pretreatment HVPG ≥12 mm Hg, 27 (69%) achieved SVR12. Four of the 33 (12%) patients with baseline HVPG ≥12 mm Hg had HVPG <12 mm Hg at the end of treatment. Of nine patients with pretreatment HVPG ≥12 mm Hg who achieved SVR12 and completed 48 weeks of follow-up, eight (89%) had a ≥20% reduction in HVPG, and three reduced their pressure to <12 mm Hg. Patients with chronic HCV and compensated or decompensated cirrhosis who achieve SVR can have clinically meaningful reductions in HVPG at long-term follow-up. (EudraCT 2012-002457-29).

P1138Cardiac shear wave velocity in healthy individuals

Background

The closure of the valves generates shear waves in the heart walls. The propagation velocity of shear waves relates to stiffness. This could potentially be used to estimate the stiffness of the myocardium, with huge potential implications in pathologies characterized by a deterioration of the diastolic properties of the left ventricle. In an earlier phantom study we already validated shear wave tracking with a clinical ultrasound system in cardiac mode.

Purpose

In this study we aimed to measure the shear waves velocity in normal individuals.

Methods

12 healthy volunteers, mean age=37±10, 33% females, were investigated using a clinical scanner (Philips iE33), equipped with a S5-1 probe, using a clinical tissue Doppler (TDI) application. ECG and phonocardiogram (PCG) were synchronously recorded. We achieved a TDI frame rate of >500Hz by carefully tuning normal system settings. Data were processed offline in Philips Qlab 8 to extract tissue velocity along a virtual M-mode line in the basal third of the interventricular septum, in parasternal long axis view. This tissue velocity showed a propagating wave pattern after closure of the valves. The slope of the wave front velocity in a space-time panel was measured to obtain the shear wave propagation velocity. The velocity of the shear waves induced by the closure of the mitral valve (1st heart sound) and aortic valve (2nd heart sound) was averaged over 4 heartbeats for every subject.

Results

Shear waves were visible after each closure of the heart valves, synchronous to the heart sounds. The figure shows one heart cycle of a subject, with the mean velocity along a virtual M-mode line in the upper panel, synchronous to the ECG signal (green line) and phonocardiogram (yellow line) in the lower panel. The slope of the shear waves is marked with dotted lines and the onset of the heart sounds with white lines. In our healthy volunteer group the mean velocity of the shear wave induced by mitral valve closure was 4.8±0.7m/s, standard error of 0.14 m/s. The mean velocity after aortic valve closure was 3.4±0.5m/s, standard error of 0.09 m/s. We consistently found that for any subject the velocity after mitral valve closure was higher than after aortic valve closure.

Conclusion

The velocity of the shear waves generated by the closure of the heart valves can be measured in normal individuals using a clinical TDI application. The shear wave induced after mitral valve closure was consistently faster than after aortic valve closure. Abstract P1138 Figure.

Abstract P1138 Figure.

Live Observation of Atherosclerotic Plaque Disruption in Apolipoprotein E-Deficient Mouse

AIM

The actual occurrence of spontaneous plaque rupture in mice has been a matter of debate. We report on an in vivo observation of the actual event of possible plaque disruption in a living ApoE(-/-) mouse.

METHODS AND RESULTS

During live contrast-enhanced ultrasonography of a 50-week-old ApoE(-/-) male mouse, symptoms suggesting plaque disruption in the brachiocephalic artery were observed. Histological analysis confirmed the presence of advanced atherosclerotic lesions with dissections and intraplaque hemorrhage in the affected brachiocephalic trunk, pointing towards plaque rupture as the cause of the observed event. However, we did not detect a luminal thrombus or cap rupture, which is a key criterion for plaque rupture in human atherosclerosis.

CONCLUSION

This study reports the real-time occurrence of a possible plaque rupture in a living ApoE(-/-) mouse.

A Cartographic Tool for Managing African Swine Fever in Eurasia: Mapping Wild Boar Distribution Based on the Quality of Available Habitats

The current African swine fever (ASF) epidemic in Eurasia represents a risk for the swine industry with devastating socio-economic and political consequences. Wild boar appears to be a key factor in maintaining the disease in endemic areas (mainly the Russian Federation) and spreading the disease across borders, including within the European Union. To help predict and interpret the dynamics of ASF infection, we developed a standardized distribution map based on global land cover vegetation (GLOBCOVER) that quantifies the quality of available habitats (QAH) for wild boar across Eurasia as an indirect index for quantifying numbers of wild boar. QAHs were estimated using a seven-level scale based on expert opinion and found to correlate closely with georeferenced presence of wild boar (n = 22 362): the highest wild boar densities (74.47%) were found in areas at the two highest QAH levels, while the lowest densities (5.66%) were found in areas at the lowest QAH levels. Mapping notifications from 2007 to 2016 onto the QAH map showed that in endemic areas, 60% of ASF notifications occurred in domestic pigs, mostly in agricultural landscapes (QAHs 1.75 and 1) containing low-biosecurity domestic pig farms. In the EU, in contrast, 95% of ASF notifications occurred in wild boar, within natural landscapes (QAH 2). These results suggest that the QAH map can be a useful epi-tool for defining risk scenarios and identifying potential travel corridors for ASF. This tool will help inform resource allocation decisions and improve prevention, control and surveillance of ASF and potentially of other diseases affecting swine and wild boar in Eurasia.

Update on the Risk of Introduction of African Swine Fever by Wild Boar into Disease-Free European Union Countries

Despite efforts to prevent the appearance and spread of African swine fever (ASF) in the European Union, several Member States are now affected (Lithuania, Poland, Latvia and Estonia). Disease appearance in 2014 was associated with multiple entrances linked to wild boar movement from endemic areas (EFSA Journal, 8, 2015, 1556), but the risk of new introductions remains high (Gallardo et al., Porcine Health Management, 1, and 21) as ASF continues to be active in endemic countries (Russian Federation, Belarus and Ukraine). Since 2014, the number of ASF notifications has increased substantially, particularly in wild boar (WB), in parallel with slow but constant geographical advance of the disease. This situation suggests a real risk of further disease spread into other Member States, posing a great threat to pig production in the EU. Following the principles of the risk-based veterinary surveillance, this article applies a methodology developed by De la Torre et al. (Transboundary and Emerging Diseases, 62, and 272) to assess the relative risk of new introductions of ASF by natural movements of WB according to the current epidemiological situation. This update incorporates the most recent available data and an improved version of the most important risk estimator: an optimized cartographic tool of WB distribution to analyse wild boar suitable habitat. The highest relative risk values were estimated for Slovakia (5) and Romania (5), followed by Finland (4), Czech Republic (3) and Germany (3). Relative risk for Romania and Finland is associated mainly with disease entrance from endemic areas such as the Russian Federation and Ukraine, where the disease is currently spreading; relative risk for Germany and Czech Republic is associated mainly with the potential progress of the disease through the EU, and relative risk for Slovakia is associated with both pathways. WB habitat is the most important risk estimator, whereas WB density is the least significant, suggesting that WB presence is more relevant than density. These results can provide actionable advice for dealing with risk. They can be directly used to inform risk-based national strategies and identify countries that may need to pay greater attention to surveillance or conduct additional evaluations at the subnational level.

Development of a new protocol for rapid bacterial identification and susceptibility testing directly from urine samples

The current gold standard method for the diagnosis of urinary tract infections (UTI) is urine culture that requires 18-48 h for the identification of the causative microorganisms and an additional 24 h until the results of antimicrobial susceptibility testing (AST) are available. The aim of this study was to shorten the time of urine sample processing by a combination of flow cytometry for screening and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for bacterial identification followed by AST directly from urine. The study was divided into two parts. During the first part, 675 urine samples were processed by a flow cytometry device and a cut-off value of bacterial count was determined to select samples for direct identification by MALDI-TOF-MS at ≥5 × 10(6) bacteria/mL. During the second part, 163 of 1029 processed samples reached the cut-off value. The sample preparation protocol for direct identification included two centrifugation and two washing steps. Direct AST was performed by the disc diffusion method if a reliable direct identification was obtained. Direct MALDI-TOF-MS identification was performed in 140 urine samples; 125 of the samples were positive by urine culture, 12 were contaminated and 3 were negative. Reliable direct identification was obtained in 108 (86.4%) of the 125 positive samples. AST was performed in 102 identified samples, and the results were fully concordant with the routine method among 83 monomicrobial infections. In conclusion, the turnaround time of the protocol described to diagnose UTI was about 1 h for microbial identification and 18-24 h for AST.

Infection and transmission heterogeneity of a multi-host pathogen (Batrachochytrium dendrobatidis) within an amphibian community

The majority of parasites infect multiple hosts. As the outcome of the infection is different in each of them, most studies of wildlife disease focus on the few species that suffer the most severe consequences. However, the role that each host plays in the persistence and transmission of infection can be crucial to understanding the spread of a parasite and the risk it poses to the community. Current theory predicts that certain host species can modulate the infection in other species by amplifying or diluting both infection prevalence and infection intensity, both of which have implications for disease risk within those communities. The fungus Batrachochytrium dendrobatidis (Bd), the causal agent of the disease chytridiomycosis, has caused global amphibian population declines and extinctions. However, not all infected species are affected equally, and thus Bd is a good example of a multi-host pathogen that must ultimately be studied with a community approach. To test whether the common midwife toad Alytes obstetricans is a reservoir and possible amplifier of infection of other species, we used experimental approaches in captive and wild populations to determine the effect of common midwife toad larvae on infection of other amphibian species found in the Peñalara Massif, Spain. We observed that the most widely and heavily infected species, the common midwife toad, may be amplifying the infection loads in other species, all of which have different degrees of susceptibility to Bd infection. Our results have important implications for performing mitigation actions focused on potential 'amplifier' hosts and for better understanding the mechanisms of Bd transmission.